<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      const a = 100;
      const b = "hello";
      const c = true;
      const d = undefined;
      const e = 100n;
      const f = {}; // 对象
      const g = Symbol(); //
      const h = null; //null
      const j = function () {};

      console.log(typeof a); // number
      console.log(typeof b); // string
      console.log(typeof c); // boolean
      console.log(typeof d); // undefined
      console.log(typeof e); // bigint
      console.log(typeof f); // object
      console.log(typeof g); // symbol
      console.log(typeof h); // object ×  null √
      console.log(typeof j); // function
    </script>
  </body>
</html>
